ctl_isc_lun_sync: Received conflicting HA LUN

Mikhail Zakharov zmey20000 at yahoo.com
Tue Apr 24 11:21:11 UTC 2018


I don’t think, adding a third node will add accuracy to BQ, and there is no network connection involved with BQ usage. Also if both nodes have stoped updating stamps, the system is dead. But the third node may be configured to handle all other issues related to any interconnections and death of BQ itself :)

WBR,
Mike

> 24 апр. 2018 г., в 14:00, Karli Sjöberg <karli at inparadise.se> написал(а):
> 
>> On Tue, 2018-04-24 at 12:32 +0300, Mikhail Zakharov wrote:
>> Hi Karli,
>> 
>> Thank you, I’m just exploring the storage abilities of my preferred
>> OS - FreeBSD. 
>> 
>> Three nodes are preferable to choose the quorum for sure, but my idea
>> was not to establish contacts between nodes. Instead of it, BQ uses a
>> small partition for the “quorum” on the same space where data volume
>> is located. 
> 
> Yes, of course. But there´s nothing you from having three nodes
> connected to the same partition and being able to make more accurate
> choices on when to take over?
> 
> If one node stops updating stamps, take over. If two nodes stops
> updating, then the problem is likely network-related and _must not_
> take over to avoid split brain. Something like that?
> 
> /K
> 
>> And if a node looses access to the quorum it means, it looses access
>> to the data volume too. Now, BQ runs on both nodes and both BQ
>> instances write stamps to the quorum partition. If for any reason BQ
>> on one node detects, the other node stops updating it’s stamps, it
>> performs failover procedure. It’s quite a questionable, rude way, I
>> can agree, and that’s why I always write a warning to use the BeaST
>> for testing only purposes. 
>> 
>> Best regards,
>> Mike
>> 
>>> 24 апр. 2018 г., в 9:09, Karli Sjöberg <karli at inparadise.se>
>>> написал(а):
>>> 
>>>>> On Mon, 2018-04-23 at 13:11 -0400, Mike Tancsa wrote:
>>>>> On 4/23/2018 12:59 PM, Mikhail Zakharov wrote:
>>>>> 
>>>>> Hello Mike,
>>>>> 
>>>>> Thank you for your interest to my paper. I appreciate it very
>>>>> much!
>>>>> Your error may be a consequence of the initial HA
>>>>> misconfiguration.
>>>>> What is in your /boot/loader.conf? Although the described
>>>>> config is
>>>>> quite simple, I can recheck the instruction in my paper in a
>>>>> couple
>>>>> of weeks only, unfortunately I’m on vacation right now.
>>> 
>>> [snip]
>>> 
>>> I read your articles on CTL HA, BQ and BeaST, and just wanted to
>>> say
>>> they are amazing, good job!
>>> 
>>> One thing I´m wondering about though is if you can claim HA with
>>> just
>>> two nodes, usually you need at least three, where the third is a
>>> tie-
>>> breaker. Otherwise with your current setup, both systems may loose
>>> contact with each other while both still being powered on, leading
>>> to
>>> potential split brain situations. What are your thoughts about
>>> that?
>>> 
>>> /K
>> 



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